Tray forming machine

ABSTRACT

A box forming machine comprises a pair of box forming dies and a double-ended ram which engages and inserts a blank into one die, and on its withdrawing movement from that die inserts a blank into the other die. The blank is initially stored in a substantially vertical stack and moved from that stack to a conveyor during which time a part of the blank is folded. The blank is then positively delivered to the die by means also effective to maintain the folded part of the blank in its folded condition.

United States Patent Cato 1 51 Feb. 1,1972

[54] TRAY FORMING MACHINE Carl F. Cato, Lynchburg, Va.

[73] Assignee: Dacam Corporation, Lynchburg, Va.

122] Filed: Apr. 11, 1969 [21] Appl. No.: 815,474

[72] Inventor:

[52] US. Cl. .93/51 R, 93/39.] P, 93/49 R, 93/59 ES, 93/59 PL [51] int.Cl. H5311 l/30, B3 lb 1/46, 133 lb 17/26 [58] Field oISearch..93/49,5l,52,59,39.l P, 93/5 1 .1

[56] References Cited UNITED STATES PATENTS 1,037,372 9/1912 Upton..93/59 1,168,462 1/1916 Batdorf "53/285 Schmiedel ..93/S9 Cahill..93/36.5 X

3,421,416 1/1969 Benzon-Petersen ..93/59 3,464,327 9/1969 Yovanovich..93/83 3,478,653 11/1969 Byrne .93/59 3,342,115 9/1967 Reinecke......93/59 3,187,648 6/1965 Tserpesw. ....93/47 3,583,295 6/1971 Elder..93/S9 Primary Examiner-Wayne A. Morse, Jr. Atmmey.lames and Franklin[57] ABSTRACT A box forming machine comprises a pair of box forming diesand a double-ended ram which engages and inserts a blank into one die,and on its withdrawing movement from that die inserts a blank into theother die. The blank is initially stored in a substantially verticalstack and moved from that stack to a conveyor during which time a partof the blank is folded. The blank is then positively delivered to thedie by means also effective to maintain the folded part of the blank inits folded condition.

19 Claims, 22 Drawing Figures PATENIEUFEB were 3.638.537

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TRAY FORMING MACHINE The present invention relates to box formingmachines, and particularly to a machine for forming setup boxes or traysfrom prescored blanks.

Machines for fonning setup boxes or trays from prescored and oftenprecut blanks are in common use to fonn the vast number of cartons,trays, boxes or the like used to package products. In these machines,blanks are placed at a loading station and are moved, as by a conveyor,to a forming die at which a ram inserts the blank into the die to foldthe blank in a predetermined manner and to overlap certain of the foldedpanels and flaps in accord with the desired construction of the finishedbox. It is common practice to apply an adhesive at appropriate locationsof the blank prior to the insertion of the blank into the die, so thatthe folding operation within the die is also effective to secureadjacent folded walls of the box to one another. Upon completion of thebox forming step, a finished box is removed from the machine.

One of the major disadvantages involved in the operation of the knownbox forming machines is that they are comparatively slow in operation.This is largely a result of the wasted motion of the conveying andforming elements in the machine during the formation of the boxes. Theram, or its equivalent, which inserts the blank into the open end of theforming die must be returned to a position from which it can then beonce again moved into engagement with the next blank at the entrance ofthe die. No useful operation is accomplished on the return movement ofthe plunger. In the great majority of these machines, the plunger movesvertically downward into the die and is then raised from the die toresume its position for a subsequent forrning operation. The downwardmovement of the plunger into the die produces an excessive amount ofnoise and vibration which develops an unpleasant environment for theworkers operating these machines, and may weaken the mechanicalconnections and upset the alignment and adjustments of the variouscomponents in the machine.

it is highly desirable for machines of this type to be readily adaptablefor fonning boxes of different sizes and shapes from blanks havingcorrespondingly different sizes and shapes. Thus, the loading stationand the box forming station, including the forming die, are preferablyadjustable.

in spite of precautions taken during the initial formation andprescoring of the blanks, some blanks occasionally are miscut so thatthe slots formed in the blank will be improperly positioned along theedges of the blank. If the miscut blank is not detected at the loadingstation and removed therefrom, the blank will be passed to the formingsection of the machine and an improper box will be formed. This willalso occur if the blanks are of the improper size or if they areimproperly oriented. The known box forming machines are generally notprovided with means to automatically detect the presence of animproperly cut, dimensioned or oriented blank and therefore they eitherrequire close inspection of the blanks at the loading station or producean impermissibly high number of rejects. The known machines also presentdifiiculties with respect to the gluing operation in that the glue isfrequently applied to the blank at locations other than those whichsubsequently overlap another folded part of the blank in the formingdie, that excessive glue subsequently being exposed on the finished box,thereby detracting from the overall appearance of that box and tendingto cause the contents inserted into the box to stick therein. Moreover,to insure the proper formation of the box in the forming die, the blank,and particularly the prefolded lines on the blank, should be insubstantial registration with the entrance of the forming die when theblank is engaged and inserted into the die by the ram. if suchregistration is not achieved, the blank will be improperly folded andthe resulting finished box will be sloppily formed and may require therejection of the box, which is wasteful of both time and money.

lt is, therefore, an object of the present invention to provide a boxforming machine which operates with improved efficiency and at greaterspeeds of box production than was heretofore possible.

It is a further object of the present invention to provide a machine forforming boxes from prescored blanks, which operates with less vibrationand noise than in the known machines of this type, and in which theboxes formed are consistently properly formed.

It is a further object of the present invention to provide a box formingmachine in which the loading station is readily adjustable toaccommodate blanks of difl'erent sizes and having difi'erently spacedslots, and which facilitates the detection of improperly formed blanksthereat, thus avoiding the conveying of these blanks to the box formingdie.

It is also an object of the present invention to provide a box formingmachine in which the boxes are formed by the insertion of a blank by aram into a forming die, in which an insertion of a blank into a die iseffected during each direction of movement of the ram, thereby toincrease the speed and efficiency at which the boxes are formed.

It is yet another object of the present invention to provide a boxforming machine in which the blanks are reliably con veyed to theforming dies and are located in substantial registration with theentrance of the die at the time the blank is engaged and inserted intothe die, thereby to insure consistently accurate formation of a box inthe die.

It is still another object of the present invention to provide a machinefor forming boxes from a plurality of prescored blanks in which theblanks are easily and reliably loaded into the machine, operation ispossible with a minimum amount of supervision, and properly formed boxesare produced in an efficient, speedy, and economical manner.

To these ends, the present invention provides a machine for formingboxes from a plurality of prescored blanks, the machine comprising apair of forming dies and a double ended ram. The ram is movable betweenpositions in which it alternately engages a blank at the entrance ofeach of the forming dies, the withdrawing movement of the ram from oneof the dies accomplishing an insertion movement of the ram, and with ita blank, into the other of the dies. A box is thus formed at eachforming die for each direction of movement of the ram, therebyincreasing the rate at which the boxes are formed.

The blanks are originally loaded in a substantially vertical stack at aloading station and are sequentially conveyed from the loading stationalong a first substantially horizontal path to a conveying station.During this movement, selected parts of the blank are engaged by afolding member interposed along that path of movement which prefoldsthese parts. The prefolded blank is engaged at the conveying station andconveyed to the entrance of the forming die by means which are alsoeffective to maintain the prefolded parts of the blank in their foldedcondition as the blank is moved. The blank conveying means is preferablyin the form of a lug carried by a reciprocating chain which comprises afirst surface engaging the blank and acting as a blank moving surface,and a second surface engaging the prefolded parts of the blank andacting as a fold maintaining surface, the lug therefore being effectiveto accomplish both fold retaining and blank feeding. Further means areprovided along the path between the conveying station and the formingdie to maintain the prefolded parts of the blank in their foldedcondition as the blank moves towards the forming die. The lug moves theblank to the forming die in a manner which insures registration of theblank with the die entrance at the time of blank insertion into the die.

The loading station of the machine of the present invention comprisesmeans for supporting the blanks in a substantially vertical orientationand comprises a rail which is adapted to be received in a slot formedalong an edge of the blank. The rail carries an enlarged part adjacentto its end which is effective to engage the blank adjacent the slot,thereby to maintain the blank in its vertical position. The loadingstation may also comprise a second support member extending below theenlarged part and engaging the blank at a position adjacent a second,lower slot formed along the same edge of the blank. To accommodateblanks having different vertical spacing between these preformed slots,the spacing between the enlarged part and rail and the support membermay be readily adjusted and set to conform to that spacing. The loadingstation may also comprise a loading plate upon which the lower edges ofthe blanks are initially placed, the relative vertical position of thatplate being adjustable so that only those blanks having a predeterminedvertical dimension between their lower edge and the upper slot (i.e.,the slot receiving the rail) will be accommodated at the loadingstation. Defective blanks, such as those which are improperlydimensioned or oriented or which have slots either missing or improperlylocated will not be simultaneously supported by the rail in such a wayas to be in proper relationship with the loading plate or the otherblanks. As a result the defective blank will be readily detected and canbe removed from the loading station so that jammed machine stoppage or awasteful forming operation on that improper blank and the subsequentrejection of the box so fon'ned are obviated.

A plurality of stripping fingers extend into the interior of each of thefonning dies and are effective to engage a doublethickness portion ofthe folded box formed in the die, that en gagement being effective toprevent the return movement of the folded box. By engaging adouble-thickness portion of the finished box along its end walls ratherthan a single-thickness portion along the sidewalls as was heretoforedone, the stripping fingers do not interfere with the movement of theram, and the formation of slots in the sides of the ram to ena ble theram to pass over the stripping fingers is not required. The relativepositions of the various folding members and the stripping fingers inthe forming die can be adjusted and set to enable the die to form boxesfrom blanks having different dimensions and configurations, thereby togreatly increase the flexibility and economy of operation of the boxforming machine.

To the accomplishment of the above, and to such other objects as mayhereinafter appear, the present invention relates to the constructionand manner of operation of a box forming machine, as defined in theaccompanying claims and as described in the specification, tal-entogether with the accompanying drawings in which:

FIG. 1 is a perspective view illustrating a prescored blank being movedfrom the loading station to the conveying station in the box formingmachine of the present invention;

FIG. 2 is a perspective view illustrating the blank as it is moved pastprefolding plates positioned in the path between the loading station andthe conveying station;

FIG. 3 is a perspective view illustrating the prefolded flap engaged bya feed lug after it has been moved by that lug to a position below thatshown in FIG. 2;

FIG. 4 is a perspective view of the prefolded blank near the lowermostportion ofits movement along the conveyor path to the forming die,illustrating the glue applicator and folding shoe provided along thatpath;

FIG. 5 is a perspective view, partly in section, illustrating the mannerin which a ram inserts the blank into the mouth of the fonning die;

FIG. 6 is a perspective view showing the folded box within the formingdie and illustrating the internally provided stripping fingers engaginga double-thickness portion of the folded box to prevent the removal ofthe folded box from the die upon the return movement of the ram;

FIG. 7 is a schematic diagram of the mechanism provided forreclprocating the conveyor and control chains and showing the feed lugsand the template carried by those chains;

FIG. 8 is atop plan view ofthe box forming machine of this inventionillustrating only one box forming section of the machine, the other boxforming section being omitted for purposes of clarity;

FIG. 9 is an elevational view, partly in cross section, showing in thesolid lines one of the box forming sections of the machine andschematically indicating by the broken lines, the other box formingsection;

FIG. I0 is an and elevation view, partly in cross section, of the boxforming machine of FIGS. 8 and 9;

FIG. II is an elevational view on an enlarged scale, of the suckerassembly used to move a blank from the loading station to the conveyorstation;

FIG. I2 is a cross-sectional view taken along the line l2 12 of FIG. ll;

FIG. 13 is an enlarged fragmentary view in vertical cross sectionillustrating the manner in which a blank is supported at the loadingstation of the machine of this invention;

FIG. 14 is a plan view, partly broken away, illustrating the manner inwhich a feed lug engages the prefolded blank as the blank is moved alongthe conveyor path to the forming die;

FIG. 15 is a view taken along the line 15-15 of FIG. I4;

FIG. I6 is a view taken along the line 16- I6 ofFIG. [4;

FIG. I) is a cross-sectional view taken along the line I7 17 of FIG. I0;

FIG. I8 is a view taken along the line l8 I8 of FIG. [7;

FIG. 19 is a partly broken away vertical cross section taken through oneof the forming dies and illustrating a blank positioned at the mouth ofthe die about to be engaged and inserted into the die by the ram;

FIG. 20 is a cross-sectional view taken along the line 20-20 of FIG. 19;

FIG. 21 is end view, partly broken away, of one sidewall of the formingdie of FIG. I9; and

FIG. 22 is a view taken along the line 22-22 of FIG. 8.

The machine of the present invention forms trays or boxes from aplurality of prescored and precut blanks of the type shown in FIGS. l-4.A typical blank of this type, generally designated 10, comprises abottom panel I2, side panels I4 and 16, and end panels I8 and 20. Cornerflaps 22, 22, and 24, 24 extend from side panels 14 and I6,respectively. To facilitate the forming and the loading of the blanks inthe machine, slots 26 and 28 are formed along each vertical edge of theblank between the end panels 18 and 20 and the corner flaps 22 and 24.Blank I0 is preferably scored or precut along horizontal fold lines 30and 30 and vertical fold lines 3] and 31 to define the lines along whichthe panels and flaps are to be folded in the formation of the finishedbox.

During that formation the corner flaps 22 and 24 are folded inwardly andthe side panels I4 and I6 are then folded up fol lowed by the folding ofend panels 18 and 20 to overlap the previously folded corner flaps 22and 24. The end panels I8, 20 and corner flaps 22, 24 may be glued toone another along their overlapping surfaces to secure the various partsof the blank in position to form the finished box as shown in FIG. 6.

The stack of blanks to be processed to form the finished boxes areinitially vertically arranged in a loading station generally designatedA (FIG. 8). A leading blank from loading station A is moved by means ofa sucker assembly generally designated B to a conveyor station generallydesignated C (FIG. 9). During movement of the blank from the loadingstation A to the conveyor station C, the upper and lower corner flaps22, 24 are prefolded (FIG. 2) so that when the blank I0 reaches theconveyor station C (FIG. 3) the comer flaps 22, 24 are already in theirfolded condition. At conveyor station C, a pair of feed lugs 34 carriedby conveyor chains 36 engage the prefolded blank and feed that blanktowards a forming station generally designated D which includes aforming die 38. The positive feeding of the lug to the die 38 presentsthe blank in registration with the mouth of the die to insure proper boxformation. A horizontally reciprocating double-ended plunger or ramgenerally designated 39 engages the blank and pushes it into forming die38. Die 38 comprises means for folding the side and end panels l4-20 ofthe blank along their respective fold lines to their final foldedpositions shown in FIG. 6. During the movement of the prefolded blankfrom conveyor station C to forming station D, flaps 22, 24 aremaintained in their prefolded condition and a quantity of glue may beapplied to end panels I8, 20 (FIG. 4) at the locations of these panelswhich subsequently overlap the flaps 22 and 24. The operating parts ofthe machine are mounted on a rigid frame generally designated E whichcomprises side frame members 4 id 43.

The folding box forming machine of the present invention may comprisetwo substantially identical forming sections located at each side of themachine. The first box forming section has already been generallydescribed. The second box forming section comprises a second suckerassembly 8', conveyor station C and a box forming station D comprising aforming die 380, the latter being arranged on a common horizontal axiswith forming die 38. Means are provided to altemately supply a prefoldedblank at the opening of each of the forming dies 38 and 38a insynchronism with the movement of the double-ended plunger 39 whichalternately engages a blank at one forming die while it withdraws (afterhaving completed a box forming operation) from the other forming die.

Means are provided to reciprocate the ram 39 between its two operativepositions, that is, the positions at which it forces a blank into firstone and then the other of the forming dies respectively, and to operatesucker assemblies B and B and the conveyor in synchronism therewith, sothat a blank is positioned at one forming die at the time the plunger 39is inserted into that forming die. As the sucker assemblies and theconveyor and box forming stations in each box forming section aresubstantially identical in construction and manner of operation, onlyone of these will be described with particularity herein, it beingunderstood that such description applies equally to the components ofboth sections.

BLANK LOADING The blanks are initially loaded at loading station A on aloading plate 40 (FIGS. 8 and 9), the lower edges of the blanks restingon plate 40. A bracket 42, secured to a vertical support member 44,comprises a rail 46 having a horizontal part 48 and a downwardly slopingpart 50. An enlarged part 52 is provided at the end of the sloping part50. A lower transverse bracket 54 is secured to vertical support 44 andhas a pin 56 extending therefrom, substantially directly beneath andparallel to the enlarged part 52. The vertical distance between thereference plane defined by the upper surface of plate 40 and thehorizontal rail portion 48 is adjustable and corresponds to the distancebetween the lower edge of the blank 10 and the location of its upperslot 26. If the blank 10 is of the proper vertical dimension and slot 26is properly formed, the slot 26 will register with rail 46 and part 48will be received within slot 26 and will be effective to support theblank 10 in a substantially vertical position on plate 40 as shown inFIG. 9. If for some reason, the blank 10 is of an improper size or ifslot 26 is either not cut, or is cut in an improper position along theedge of the blank, or if the blank is not properly oriented, the slot 26will not register with the rail 46 when the blank 10 rests on supportplate 40 so that the improperly dimensioned or miscut blank will not besupported by rail 46 at loading station A and will thus be readilydetected and reoriented or removed.

A properly dimensioned and cut blank is then moved over the horizontalpart 48 of rail 46 until it reaches the onset of sloping part 50. Theblank then proceeds to slide along rail 46 until it abuts against theenlarged part 52 at a position above slot 26, its lower portion thenresting against the pin 56, which engages the blank adjacent its slot 28(FlG. 13). At this time, the lower edge of the leading blank 10 may reston or be spaced above the upper surface of brake bracket 60, and will besupported in a substantially vertical position by the engagement of theenlarged part 52 and pin 56 with the blank adjacent the upper and lowerslots 26 and 28. A plurality of blanks are so loaded and form a stack ofblanks near sucker assembly B as at II. The upper slot 26 of each blankreceives the sloping part 50 of rail 46; only the leading blank 10aengages enlarged part 52 and pin 56. A second stack of blanks (notshown) is formed in a similar manner near the other sucker assembly 5.

To accommodate blanks of different sizes and different spacing betweenthe upper and lower slots 26 and 28, the relative vertical positions ofloading plate 40 and rail 46 (and thus enlarged part 52) are adjustable.To this end, slots 62 and 64 are formed in vertical support 44, bracket42 being secured to vertical support 44 by a fastener 64 which passesthrough slot 62 and strut 66, secured at one end to the support plate40, is secured at its other end to vertical support member 44 by meansof a fastener 68 passing through slot 64. Thus the vertical distancebetween the support plate 40 and the rail part 48 and the enlarged part52 may be set to accommodate the particular sized and cut blanks loadedat loading station A. The adjustment of the position of bracket 42 alsodetermines the distance between enlarged part 52 and pin 56 so thatblanks having varying distances between the slots 26 and 38 may besupported by part 52 and pin 56 at stack ll. As seen in FIG. 8, a pairof such brackets 42 each having a rail 46 and an enlarged part 52 arearranged at the front and rear of the machine to receive the slots 26,28 in the end panels l8 and 20. A second lower pin 56 is also providedbelow the second enlarged part 52 but cannot be seen in FIG. 8.

The vertical position of brake bracket 60 may be adjusted to correspondto the distance between the lower slot 28 and the lower edge of theblank, i.e., the height of corner flap 24.

INITIAL BLANK MOVEMENT AND PREFOLDING The leading blank 10a in stack I]is moved to the conveyor station C by means of the sucker assembly B.Sucker assembly B comprises four sucker rods 70 which are moved inunison into and out of engagement with the leading blank by theoperation of a sucker operating mechanism generally designated 72, theoperation of which is more completely described below. When the suckerarms 70 are moved into position to engage leading blank 10a as shown inFIG. 2 and by the broken lines in FIG. 8, a vacuum is created at theends of the sucker arms 70 to create a suction force enabling the suckerarms to securely grasp the leading blank llJa. When the sucker arms 70are then moved back (to the right in FIGS. 8 and 9) towards theiroriginal position, the leading blank 10a is pulled over the restrainingenlarged part 52 and pin 56 is moved towards conveyor station C. Whenthe sucker arms 70 reach the furthermost position away from the stack iiand the blank 10a is positioned at the conveyor station C, the vacuumpressure, and thus the suction force between the sucker arms 70 and theblank 10a, is removed.

Two pairs of opposing arcuate bending plates 74, 74 and 76, 76 arepositioned in the path of movement of leading blank 100 from the stack11 to the conveyor station Cv When the blank is moved by the sucker arms70 past bending plates 74 and 76, the plates respectively engage theupper and lower corner flaps 22 and 24 to fold these flaps along theirfoldlines 31 and 31'. At the time the blank reaches the conveyor stationC, all four of the comer flaps 22 and 24 are in folded condition (FIG.2).

The upper folding plates 74 are secured to brackets 78 which are in turnsecured to brackets 42 so that the adjustment of the vertical positionof the latter. which as described above adjusts the loading station A toreceive blanks of different vertical dimensions, also effects adjustmentof the verti cal position of the upper folding plates 74. Hence theplates 74 are substantially at the level of the upper corner flaps 22 asthe blank passes thereby on its way to the conveyor station C. The lowerfolding plates 76 are secured to bracket 54 which car ries the pin 56 sothat the vertical distance between the upper and lower folding plates74, 76 is correlated to the vertical distance between the enlarged pan52 and the pin 56 and thus to the spacing between the upper and lowercorner flaps of the blank.

BLANK CONVEYING The conveyor station C, which receives the blank in itsprefolded condition, comprises a pair of spaced vertically reciprocatingchains 36 passing around upper and lower sprocket wheels 80 and 82, eachchain 36 carrying a feed lug 34, and a third vertically reciprocatingchain 84 passing around upper and lower sprocket wheels 86 and 88 andcarrying a template I00. The vertical motion of the chains 36 and 84 issynchronized with the horizontal movement of sucker assembly B toposition the feed lugs 34 directly above the upper edges of end panels18 and 20 of the blank at the time the blank has been moved to itsmaximum extent away from the stack II by means of the sucker arms 70, atwhich time, it will be recalled, the suction force between the blank andsucker arms 70 is removed.

As seen in FIG. 3 and FIGS. 14-16, lugs 34 are in the form of a verticalflat part 90 which partially engages or abuts against the prefoldedcorner flap 22, and a horizontal edge part 92 which abuts against theupper edge of one of the end panels 18 and 20. A tapered finger segment93, contiguous with surface 90, extends over the end panels 18 and 20 torestrain the blank in a vertical position. As the chains 36 are moveddownwardly, the engagement of the lug edge parts 92 with the upper edgesof panels 18 and 20 urge the blank downward, and the engagement of thelarger vertical parts 90 against the prefolded corner flaps 22 and 24maintain those flaps in their folded position (FIGS. 3).

Lower folding plates 76 each have a fold retaining bracket 94 dependingtherefrom. A pair of fold retaining shoes 96 is positioned along thepath of movement of the prefolded blank below the lower end of brackets94. As the blank is urged downward by the feed lugs 34 the upper cornerflaps 22 pass by the upper folding plates 74 and approach the upper endof lower folding plates 76, and the folded lower corner flaps 24 pass bybrackets 94 and are engaged by shoes 96. As the blank moves furtheralong its downward path the upper corner flaps 22 are engaged by thelower end of bracket 94 and the lower flaps 24 continue to be engaged byshoes 96 (FIG. 4). As the blank urged by lugs 34 moves still furtherdownward, both upper and lower flaps 22 and 24 engage the shoes 96 untilthe blank reaches its lowermost point along the conveyor path, at whichtime the blank is positioned directly in front of and in registrationwith the mouth of forming die 38 (FIG. 5). An adjustable stop 98 ispositioned near the entrance of the forming die 38 and engages the loweredge of end panels I8 and to prevent further downward movement of theblank. The frictional engagement between the brackets 60 and 94 and theshoes 96 on the one hand and the prefolded corner flaps 22 and 24 on theother hand is effective to limit the rate at which the blank movestowards the forming die and prevents the blank from freely falling afterthe suction force of the sucker arms 70 is released therefrom.

It will be noted in FIG. 3, that the edge parts 92 of the lugs 34 engageend panels I8 and 20 along edges that are coiinear with the upperfoldline 30 along which the upper side panel 14 is to be folded atforming die 38. As the extent of travel of chains 36 and lugs 34 can beaccurately controlled, the positive blank feed by lugs 34 to the formingdie 38 insures that the foldline 30 will be positioned in substantialregistration with the mouth of that die, thus in turn insuring that theside panel 14 of the blank will be accurately folded along foldline 30.The lower side panel foldline 30' necessarily will be in registrationwith its folding member in forming die 38 when the upper foldline 30 isso positioned, so that side panel 16 will be similarly accurately foldedalong its foldline 30.

While the blank is moving from the conveyor station C towards theentrance of the forming station I), a controlled quantity of glue isapplied at specified locations along end panels I8 and 20, so that whenthese panels are folded over the corner flaps 22 and 24 in forming die38, the glue will set and secure these parts to one another, thereby tosecure the box in its desired condition. For this purpose, template I00is carried on the outer flight of chain 84 which reciprocates insynchronisrn with chains 36. The lugs 34 are on the inner flight ofchains 36, so that as the lugs 34 move downward template 100 will moveupwards, and vice versa. A first photocell assembly I02 is arranged inthe upper part of the path of movement of the template I00, and a secondphotocell assembly 104 is arranged at the lower part of the path ofmovement of lugs 34 and the blank towards the forming station D (seeFIG. 9). The photocell assemblies I02 and 104 are in operativeconnection with an amplifier and solenoid control switch (not shown) andare effective when the light beams of both pairs of photocell assembliesare interrupted to trigger that switch to operate a pair of'gluesprayers I06 arranged along the path of the blanks movement in alignmentwith the end panels I8 and 20. The glue sprayers I06 are mounted onhorizontally adjustable brackets 107 and the lower photocell assemblyI04 is mounted on a bracket I08 the vertical position of which isadjustable to enable glue sprayers 106 to be accurately positioned tosupply a controlled amount of glue at the appropriate locations onblanks of varying dimensions. As seen best in FIG. 9, the upperphotocell assembly 102 is displaced to the right of the lower photocellassembly I04. The reciprocating movement of chains 36 and 84, whichrespectively guide the blank towards the forming station D and carry thetemplate I00, will cause the blank to interrupt the light beam of thelower photocell assembly I04, and the template 100, during its motion,which, as noted above, is opposite in direction to that of feed lugs 34,will interrupt the light beam of the upper photocell assembly I02. Asseen in FIG. 18, template comprises a series of spaced teeth IOI so thatwhen chain 84 moves template 100 through photocell assembly 102 itslight beam is periodically interrupted by the teeth 101. As a result,glue sprayer I06 will be actuated once for each of the teeth 101 oftemplate 100 during the downward motion of the blank towards the formingstation D, thereby to deposit globules of glue along end panels 18 and20 as shown at I08 and 109 in FIG. 4.

During the upward motion of chains 36 to return feed lugs 34 to aposition to engage the next blank from the stack, no blank is carried bychains 36. As a result, even though the teeth 10! of template I00 (nowmoving downward) once again interrupt the beam of light of upperphotocell assembly 102, that interruption will not be effective tooperate the glue sprayers I06, since the light beam through the lowerphotocell assembly I04 remains uninterrupted (there is no blank to dothe interrupting). Glue sprayers I06 will thus only be operated when ablank is carried down by the conveyor chains 36 and feed lugs 34 towardsthe forming station D.

To summarize, the prefolded blank from loading station A is conveyeddownwardly from the conveyor station C to the blank forming station Dwhile the upper and lower corner flaps 22 and 24 are folded, these flapsbeing at all times maintained in their folded condition while the blankis so conveyed. During the movement of the prefolded blank, a controlledquantity of glue is deposited at selected locations along the end flapsI8 and 20 of the blank. The foldlines 30 and 30' along which the sideflaps I4 and 16 are to be respectively folded are aligned with theforming elements in the die as a result of the positive feed of theblank by the feed lugs 34 along an edge which is colinear with the upperfoldline 30, and by the adjustable positive stops 98. when the blank isin front of the mouth of the forming die 38, the prefolded corner flaps22 and 24 are maintained in their folded condition by their engagementwith the lower part of the folding shoes 96.

BOX FORMATION A prefolded and glued blank is inserted into the mouth ofthe forming die 38 by the operation of ram 39 which comprises a plungerI10 carrying a forming head I I2 and 1120 on each of its ends (FIG. 9).When head "2 engages and inserts a blank into forming die 38, head I iswithdrawn from forming die 38a (shown in broken lines in FIG. 9), andwhen forming head 112 is withdrawn from forming die 38, forming head1120 is moved into forming die 38a to engage and insert a blank and forma box thereat. Forming dies 38 and 380 are substantially similar inconstruction and are arranged along a common horizontal axis which alsodefines the axis of reciprocatory motion of plunger IIO, the latter thusbeing ef' fective to alternately insert and withdraw forming heads 112and 112a into forming dies 38 and 380 respectively. Only forming die 38will be described herein, it being understood that this descriptionapplies equally to forming die 380.

As seen best in FIGS. 5, 9 and 19, the forming die 38 comprises a pairof sets of folding fingers 114 and 116 which respectively engage andfold side panels 14 and 16 as the blank is moved into the die by the ram39. Located outboard of fingers 114 and 116 (in the axial direction ofmovement of ram 39) are the end panel folding plates 118 which, as theblank is inserted further into the die, engage and fold the end panels18 and 20 as the blank passes thereby. The end panels 18 and 20, whichcarry the glued portions 108 and 109, are folded over the folded cornerflaps 22 and 24 and are adhered thereto. The overlapping of the endpanels 18 and 20 and the comer flaps 22 and 24 form a double-edgedthickness of the box (FIG. 6) as distinguished from the single-edgethickness of the remainder of the finished box. Outboard of foldingplates 118, two sets of strippers 120 project into the interior of die38. They are provided with radially inwardly and axially outwardlyinclined carnming surfaces which permit the folded box to pass thereovertowards the exit of the forming die 38, the strippers 120 then engagingthe double-thickness portion of the folded box after the folded box haspassed thereover, thereby to prevent the reverse movement of thefinished box back towards the entrance of the forming die when the ram39 is moved out of the die. These strippers 120 thus are effective toremove the finished box from the forming head 112. Strippers 120 engagethe folded blank only along the double-edge thickness portion of the box(i.e., where end panels 18 and 20 overlap comer flaps 22, 24), but needextend into the interior of the forming die 38 only substantially to theextent of the thickness of a single edge. As a result, the forming head112 is able to move freely past the strippers 120 without having toprovide slots in the sidewalls of the head 112.

A given finished box remains in the interior of the forming die 38outboard of the strippers 120. The formation of the next box in thatforming die is effective to move the previously formed box outwardtowards the exit of the forming die 38 from which the box falls or issubsequently removed. While the finished box is in the forming die 38,the panels 18, 20 are pressed against the corner flaps 22, 24, so thatthe glue on the side panels 18 and 20 has the opportunity to set. Hence,when a given box is removed from the forming die it is ready forshipment and packing.

The vertical position of the lower wall 122 of the forming die 38, alongwith the folding member 116 carried thereby, may be varied by looseninga fastener 124 passing through a vertical slot provided in support 126(FIG. 19). Wall 128 may be also either raised or lowered to vary therelative vertical position of the upper forming member 114 in a similarmanner. The blank stop 98 is a threaded member passing through anopening in plate 130. The strippers 120, in two sets of four stripperseach, extend into the interior of die 38 through a series of parallelslots 121 formed in a pair of end walls 123 from which folding members118 extend. Each set of strippers 120 is secured to a spring 125 (FIG.21) clamped between element 127 and spacer 129, the spacer 129 in turnbeing mounted on a vertical bracket 131. An adjustment screw 133 passesthrough an opening in bracket 131 and engages a nut 133 having anannular flange 135 extending into longitudinal channels 141 formed in apair of rails 137 and 139 extending longitudinally along die 38. Whennut 133' is loosened, bracket 131 may be moved along channels 14],thereby to move strippers 120 along slots 121 to a desired positioncorresponding to the depth of the finished box, after which nut 133 istightened to maintain bracket 131 and strippers 120 in that position. Inthis manner the strippers 120 may be accurately positioned within die 38to remove finished boxes of varying depths from the withdrawing ram 39.

The sidewalls of the forming die which carry the folding members 118 andthe strippers 120 are also mounted so as to be adjustable to accommodateblanks of varying widths, and

particularly blanks having different transverse dimensions between theirend panel foldlines 31 and 31 The folding and stripping elements offorming dies 38 and 380 can thus be readily adjusted and set for boxforming operations on a great variety of blank types, to form finishedboxes of differing sizes and shapes. The overall flexibility of themachine thus is greatly increased without the need for replacing theforming die for different boxes, and hence without a significantincrease in the complexity and cost of the machine.

RAM MOVEMENT As described above, ram 39, which alternately inserts theblanks in the forming dies 38 and 38a, is driven in synchronism with theblank moving mechanism so that when a blank is presented at the mouth ofa forming die, the ram is moving in a direction to insert the blank intothat die.

The driving energy for the various mechanisms of the machine is providedby an electric motor 131 [see FIG. 7] which is operably connected to agear or drive box 132 having an output shaft 134, joumaled in a bearingI35 mounted on end wall 41. Shafi 134 carries a crank 136 [see FIGS. 8and 9] which has a pin 138 secured to its free end which in turn carriesa roller 140. Roller 140 is free to move vertically along a scotch yoke142 which is secured to the transverse plunger 1 10 of the ram 39. Thus,as shaft 134 rotates, roller 140 moves along a circular path and actsagainst the scotch yoke 142 to impart transverse motion to plunger 110first in one direction, as it rotates between its two extreme horizontalpositions in one direction (e.g., from left to right), and then in areverse transverse direction, as the roller moves between its extremehorizontal positions in the opposite direction (e.g., from right toleft). Reciprocating motion is imparted to plunger 110 and to ram 39 tocause one head, e.g., 112, of the ram 39 to first enter forming die 38,and then as that head leaves forming die 38, the other head 112a isinserted into the other forming die 38a.

Shaft 134 also carries a cam 146 which rotates therewith. A cam follower148, carried on a rocker arm 150, which is pivotally mounted at itslower end on a pin 152, engages cam 146 and is springloaded thereagainstby a suitable biasing spring [not shown]. Arm 150 at its upper arm issecured at a joint 154 to the ends of two transverse rods 156 and 158which are operatively connected respectively to the sucker arm operatingmechanisms 72 and 72a provided at each end of the machine to produce thealternating reciprocating motion of the sucker arms 70. As the manner inwhich rods 156 or 158 are connected to their respective sucker operatingmechanisms is identical, only one such connection will be describedherein (i.e., the mechanism 72 operatively connected to rod 156). Acrank 160 is pivotally connected to one end of rod 156 by pin 162 andits other end is fast on shaft 166, which is in turn fast to crank 168,crank 168 being connected at its upper end to an arm 170 which in turnis pivotally connected to a sucker carriage 172 by pin 173.

As seen best in FIGS. 11 and 12, sucker carriage 172 carries asupporting post 174 which carries transverse arms 175 and 176 which inturn carry sucker arms 70 at their ends. Carriage 172 also includesupper and lower brackets 177 and 178 to which rollers 180 and 182 arerespectively rotatably mounted. Two additional rollers 184, rotatableabout an axis perpendicular to the axes of rotation of rollers 180 and182, are mounted centrally along the carriage 172. The roller 182 isreceived in and moves along a longitudinal channel 188 formed in guiderail 186. As shown in FIG. 12. rollers 180 and 182 engage opposingsurfaces of the rail I86 and allow car riage 172 to move therealong whenan appropriately directed force is applied to arm 170.

The rotation of shaft 134 causes can 146 to rotate, thus causing arm 150to pivot about pin 152, thereby causing reciprocatory motion of rod 156.Crank 160 is then pivoted about pin 162 to impart a rocking motion toshaft 166 which in turn causes crank 168 to pivot. That movement ofcrank 168 applies a transverse force to arm 170 which causes carriage172 to move along rail channel 188. As a result sucker post 174 andsucker arms 70 will move in a direction either to or from the stack ofblanks depending on the direction of movement of rod 156, which in turnis determined by which portion of cam 134 is engaging the cam follower148 at that time. It will be seen that rods 156 and 158 reciprocate inthe same direction so that as the carriage 172 of sucker assembly B ismoving outwards, that is away from the stack to pull a blank from thestack to the conveyor station C, the other sucker assembly B operativelyconnected to rod 158 is moved from the conveyor station C towards theother stack of blanks on its way to remove a blank therefrom.

As seen best in FIG. 22 an outwardly extending arm 190 is secured toshaft 134 and a pair of switches 192 and 194 are transversely spacedalong a support plate 195 in the path of movement of am 190 as itrotates along with the shaft 134. Switches 192 and 194 are periodicallyactuated when the end of crank 190 engages the pivoting contact members196 of each switch. Switches 192 and 194 are in respective circuitconnection with solenoids 198 provided in each of sucker assemblies Band B. As shaft 134 rotates, these solenoids are alternately energizedthrough actuation of switches 192 and 194, to connect their associatedsucker arms 70 with a source of vacuum, operatively connected theretovia tubes 200. The timing is such that each sucker assembly B and B isvacuumized only from its time of engagement with the leading blank 100at loading station A to the time that it has moved that blank to theconveying station C.

As seen in FIG. 7, shaft 134 also carries a sprocket wheel 202 aboutwhich a chain 204 passes, chain 204 also passing over a smaller diametersprocket wheel 206 fast on shaft 208. Also mounted on shaft 208 is asprocket wheel 210 about which an endless chain 212 passes, that chainalso passing over a second sprocket wheel 214 mounted on shaft 216. Oneend of a rod 218 is secured to chain 212. Its other end is also securedto a chain 220, chain 220 passing over sprocket wheels 222, 224, 226,228, 230 and 232. Sprocket wheel 230 is fast on shaft 234 which alsocarries sprocket wheels 82 and 88 of the chain system associated withconveyor station C and sprocket wheel 224 is fast on shaft 236 whichcarries the lower sprocket wheels 82a and 88a of the chain systemassociated with conveyor station C. Thus, rotation of sprocket wheel 230causes movement of chains 36 and 84 and the rotation of sprocket wheel224 causes the movement of chains 36a and 84a.

in operation, the rotation of shaft 134 in a counterclockwise directioncauses wheel 202, and chains 204 and 212 to rotate in a counterclockwisedirection and causes rod 218 and chain 220 to move laterally towards theleft (as viewed in FIG. 7). That movement of chain 220 imparts aclockwise rotation to sprocket wheel 232 and a counterclockwise rotationof sprocket wheel 230. The latter rotation in turn causes acounterclockwise rotation of shaft 234 and thus of sprocket wheels 82and 88 which will in turn cause feed lugs 34 to move in a downwarddirection and cause template 100 to move in an upward direction. In asimilar manner, sprocket wheel 222 will be caused to rotate in aclockwise direction causing a counterclockwise rotation of sprocketwheel 224 and shaft 236, which in turn will cause the feed lugs 36a tomove in an upward direction and the template 1000 to move in a downwarddirection.

When rod 218 has passed around the sprocket wheel 210, and is thenmoving towards the right, along the lower flight of its path towardssprocket wheel 214, as shown by dotted rod 218a in FIG. 7, the directionof movement of rod 218 is reversed, and the movements of chain 220, feedlugs 34, 34a, and templates 100, 1000 are respectively reversed. Thus itwill be seen that the operation of the chain drive mechanism impartsvertical reciprocatory movement in opposite directions to the feed lugs34 [and 34a] and templates 100 [and 100a] of the two chain drivesystems, these chain systems thus operating essentially I80 out of phasewith one another. As the chain systems are both operatively driven bythe common shaft 134, which also drives the sucker assemblies H and Band the ram 39, the movements of all mechanisms involved in moving andforming the blank in each box forming section are positivelysynchronized, and the desired displacement of blank forming operationsin each of the forming sections is achieved.

SUMMARY OF OPERATION The sucker assembly (B or B) is first moved towardsthe blank by means of the sucker operating mechanism (72 or 72') andwhen the sucker arms 70 reach the leading blank in the stack, the propersolenoid switch (192 or 194) is actuated and vacuum pressure is appliedto the end of sucker arms 70 in the appropriate sucker assembly to graspa blank from the appropriate stack. The direction of movement of suckerarms is then reversed and the sucker arms, still grasping the leadingblank, are moved towards the conveying station C or C during which timethe comer flaps of the blanks are folded. When the blank arrives at theconveying station the vacuum pressure is removed from the sucker arms,and the feed lugs are moved downward further to engage the upper edgesof the end panels of the blank and to move the blank downwards to themouth of the forming die [38 or 38']. During this movement glue isapplied to the blank. The ram 39 is then reciprocated to engage thatblank and insert it into the forming die, thereby to fold the side andend panels of the blank into their condition to form the finished box.While this is occurring, the sucker moving mechanism and chain drive ofthe other box forming station are operating in the reverse direction,that is, the feed lugs are moving upwards away from the forming die backtowards the upper end of the conveyor station, the sucker arms are nowbeginning to move outward towards the other stack to engage a new blankfrom that stack, and the direction of the ram is away from the otherforming die to withdraw the other forming head from that forming die.Further rotation of shaft 134 is then effective to once again reversethe operation of the various sucker, chain and ram mechanisms, to bringabout blank positioning and box forming at the other section of themachine, while the section of the machine at which the box was justformed is being readied for a new box forming operation.

The present invention has thus provided a box forming machine whichforms finished boxes at two opposed box forming stations utilizing asingle ram having forming heads at both of its ends. The insertion ofthe ram into one of the forming dies pushes a blank in that die to formthe box and the withdrawal of the ram from that die is effective to pusha blank into the other of the forming dies to form a box thereat. As aresult, both the speed and efficiency of the box forming operation areincreased. The blank is conveyed to the mouth of the forming die inprecise registration with the opening of the die to assure that thefolding operation will be performed along the desired fold lines so thata neat box will be consistently formed by the machine. As ram movementand blank insertion are effected horizontally, the operation of themachine is relatively quiet and free from vibration. The various loadingand forming elements in the machine may be readily adjusted toaccommodate blanks of different sizes and folding configurations toincrease the flexibility of the machine in forming boxes ofcorrespondingly different sizes and shapes. Moreover, the loading of theblanks in the machine is facilitated, and provides means for detectingthe presence of miscut or improperly dimensioned or oriented blankswhich can be quickly rejected at the loading station, thus avoiding thewasteful effort involved in the manufacture of boxes which will have tobe subsequently rejected. As a result a properly and neatly formed andglued box is insured at both the forming dies with a minimum amount ofsupervision and adjustment to the machine elements. The machine formsboxes and trays from blanks in a more efficient and economical mannerthan was heretofore possible in machines of this type.

While one major advantage of the machine here described is itsdouble-ended action, that is not its only advantage, and it will beappreciated that where a high rate of productivity is not a factor onlyone set of loading station, conveyor station and forming die can beprovided, such a single-ended machine still exhibiting others of theadvantages of the disclosed mechanisms.

While only a single embodiment of this invention has been hereinspecifically disclosed, it will be apparent that variations may be madethereto without departing from the spirit and scope of the invention asdefined in the following claims:

1. A machine for forming boxes from blanks, said machine comprising,first and second forming stations, means for supplying blanks to each ofsaid forming stations, unitary plunger means having first and secondoppositely facing blank engaging members at each of its ends, means forreciprocating said plunger means between a first position at which saidfirst member engages a blank at said first forming station and a secondposition at which said second member engages a blank at said secondforming station, and means for operating said blank supplying means andsaid plunger reciprocating means in a predetermined timed relationship,whereby two blanks are formed into boxes during each completereciprocation of said plunger means.

2. The box forming machine of claim 1, in which said supplying meanscomprises means for alternately supplying blanks to said first andsecond forming stations.

3. The box forming machine of claim 2, in which said form ing stationsare arranged substantially along a common axis, and said plunger meansis substantially horizontally arranged, said plunger moving meanscomprising means for reciprocating said plunger means substantiallyalong said axis.

4. The box forming machine of claim 3, in which said machine comprisinga blank loading station located above said forming station and anintermediate station spaced from said loading station, said supplyingmeans comprising means for moving a blank along a first substantiallyhorizontal path from said loading station to said int :rmediate station,and then along a second substantially vertical path from saidintermediate station to said forming station.

5. The box forming machine of claim 4, comprising means positioned alongsaid first path and effective to engage and fold a predetermined part ofsaid blank as said blank moves along said first path from said loadingstation to said intermediate station.

6. The box forming machine of claim 5, comprising means positioned alongsaid second path and effective to engage and maintain said blank part inits folded condition as the blank is moved along said second path.

7. The box forming machine of claim 5, in which said means for movingsaid blank along said second path includes means effective to maintainsaid blank part in its folded condition.

8. The box forming machine of claim 7, in which said means for movingsaid blank along said second path comprises a movable member having afirst surface engaging an unfolded part of said blank, and a secondsurface engaging the folded part of the blank, said second surfacecomprising said fold maintaining means.

9. The box forming machine of claim 8, in which said blank is providedwith a fold line at which said blank is to be folded in said formingstation, said first surface of said member engaging said blank along anedge substantially colinear with said fold line, thereby to insure thatsaid blank is moved to a position in which it is in substantial registrywith said plunger means and said forming means.

10. The box forming machine of claim 1, in which said machine comprisesa blank loading station located above said forming station and anintermediate station spaced from said loading station, said supplyingmeans comprising means for moving a blank along a first substantiallyhorizontal path from said loading station to said intermediate station,and then along a second substantially vertical path from saidintermediate station to said forming station.

ll. The box forming machine of claim 10, comprising means positionedalong said first path and effective to engage and fold a predeterminedpart of said blank as said blank moves along said first path from saidloading station to said intermediate station.

12. The box forming machine of claim 11, in which said means for movingsaid blank along said second path includes means effective to maintainsaid blank part in its folded condition.

13. The box forming machine of claim 11, comprising means positionedalong said second path and effective to engage and maintain said blankpart in its folded condition as the blank is moved along said secondpath.

14. The box forming machine of claim [2, comprising means positionedalong said second path and effective to engage and maintain said blankpart in its folded condition as the blank is moved along said secondpath.

15. The box forming machine of claim [2, in which said means for movingsaid blank along said second path comprises a movable member having afirst surface engaging an unfolded part of said blank and a secondsurface engaging the folded part of the blank, said second surfacecomprising said fold maintaining means.

16. The box forming machine of claim 15, in which said blank is providedwith a fold line at which said blank is to be folded in said formingstation, said first surface of said member engaging said blank along anedge substantially colinear with said fold line, thereby to insure thatsaid blank is moved to a position in which it is in substantial registrywith said plunger means and said forming means.

17. The box forming machine of claim I, in which said blank has an endpanel, said forming stations each comprising an entrance and an exit,means effective to fold said end panel over said folded part to providea double-thickness portion of a box, and means operatively secured tothe interior of said forming station inward of said entrance andeffective to permit the folded box to pass thereover towards said exitin response to the inward movement of said plunger means into said forming station and effective to engage said double-thickness por tion oncesaid folded box has passed thereover, thereby to prevent the folded boxfrom returning towards said entrance in response to the return movementof said plunger means away from said forming station.

18. In a machine for forming boxes from blanks having opposed foldableend panels and opposed foldable flaps of a given thickness, said machinecomprising box forming means including means effective to fold said endpanel and said flap into overlying relationship and to secure them inthat relation ship, thereby to form a portion ofa folded box having adouble thickness, said forming means comprising a forming station havingan entrance and reciprocating means for urging said blank into andthrough said forming station, and means operatively secured to aninterior surface of said forming station at a location inboard of saidentrance and effective to engage said double-thickness portion of saidbox after said box has passed thereby, thereby to prevent returnmovement of said folded box towards the entrance of said formingstation, during the return stroke of said reciprocating means.

19. In a machine for forming boxes from blanks having opposed foldableend panels and opposed foldable flaps of a given thickness, said machinecomprising box forming means including means effective to fold said endpanel and said flap into overlying relationship and to secure them inthat relation' ship, thereby to form a portion of a folded box having adouble thickness, said forming means comprising a forming station havingan entrance and reciprocating means for urging said blank into andthrough said forming station, and means operatively secured to aninterior surface of said forming station at a location inboard of saidentrance and effective to engage said double-thickness portion of saidbox after said box has passed thereby, thereby to prevent returnmovement of said folded box towards the entrance of said formingstation, during the return stroke of said reciprocating means, saiddouble-

1. A machine for forming boxes from blanks, said machine comprising,first and second forming stations, means for supplying blanks to each ofsaid forming stations, unitary plunger means having first and secondoppositely facing blank engaging members at each of its ends, means forreciprocating said plunger means between a first position at which saidfirst member engages a blank at said first forming station and a secondposition at which said second member engages a blank at said secondforming station, and means for operating said blank supplying means andsaid plunger reciprocating means in a predetermined timed relationship,whereby two blanks are formed into boxes during each completereciprocation of said plunger means.
 2. The box forming machine of claim1, in which said supplying means comprises means for alternatelysupplying blanks to said first and second forming stations.
 3. The boxforming machine of claim 2, in which said forming stations are arrangedsubstantially along a common axis, and said plunger means issubstantially horizontally arranged, said plunger moving meanscomprising means for reciprocating said plunger means substantiallyalong said axis.
 4. The box forming machine of claim 3, in which saidmachine comprising a blank loading station located above said formingstation and an intermediate station spaced from said loading station,said supplying means comprising means for moving a blank along a firstsubstantially horizontal path from said loading station to saidintermediate station, and then along a second substantially verticalpath from said intermediate station to said forming station.
 5. The boxforming machine of claim 4, comprising means positioned along said firstpath and effective to engage and fold a predetermined part of said blankas said blank moves along said first path from said loading station tosaid intermediate station.
 6. The box forming machine of claim 5,comprising means positioned along said second path and effective toengage and maintain said blank part in its folded condition as the blankis moved along said second path.
 7. The box forming machine of claim 5,in which said means for moving said blank along said second pathincludes means effective to maintain said blank part in its foldedcondition.
 8. The box forming machine of claim 7, in which said meansfor moving said blank along said second path comprises a movable memberhaving a first surface engaging an unfolded part of said blank, and asecond surface engaging the folded part of the blank, said secondsurface comprising said fold maintaining means.
 9. The box formingmachine of claim 8, in which said blank is provided with a fold line atwhich said blank is to be folded in said forming station, said firstsurface of said member engaging said blank along an edge substantiallycolinear with said fold line, thereby to insure that said blank is movedto a position in which it is in substantial registry with said plungermeans and said forming means.
 10. The box forming machine of claim 1, inwhich said machine comprises a blank loading station located above saidforming station and an intermediate station spaced from said loadingstation, said supplying means comprising means for moving a blank alonga first substantially horizontal path from said loading station to saidintermediate station, and then along a second substantially verticalpath from said intermediate station to said forming station.
 11. The boxforming machine of claim 10, comprising means positioned along saidfirst path and effective to engage and fold a predetermined part of saidblank as said blank moves along said first path from said loadingstation to said intermediate station.
 12. The box forming machine ofclaim 11, in which said means for moving said blank along said secondpath includes means effective to maintain said blank part in its foldedcondition.
 13. The box forming machine of claim 11, comprising meanspositioned along said second path and effective to engage and maintainsaid blank part in its folded condition as the blank is moved along saidsecond path.
 14. The box forming machine of claim 12, comprising meanspositioned along said second path and effective to engage and maintainsaid blank part in its folded condition as the blank is moved along saidsecond path.
 15. The box forming machine of claim 12, in which saidmeans for moving said blank along said second path comprises a movablemember having a first surface engaging an unfolded part of said blankand a second surface engaging the folded part of the blank, said secondsurface comprising said fold maintaining means.
 16. The box formingmachine of claim 15, in which said blank is provided with a fold line atwhich said blank is to be folded in said forming station, said firstsurface of said member engaging said blank along an edge substantiallycolinear with said fold line, thereby to insure that said blank is movedto a position in which it is in substantial registry with said plungermeans and said forming means.
 17. The box forming machine of claim 1, inwhich said blank has an end panel, said forming stations each comprisingan entrance and an exit, means effective to fold said end panel oversaid folded part to provide a double-thickness portion of a box, andmeans operatively secured to the interior of said forming station inwardof said entrance and effective to permit the folded box to passthereover towards said exit in response to the inward movement of saidplunger means into said forming station and effective to engage saiddouble-thickness portion once said folded box has passed thereover,thereby to prevent the folded box from returning towards said entrancein response to the return movement of said plunger means away from saidforming station.
 18. In a machine for forming boxes from blanks havingopposed foldable end panels and opposed foldable flaps of a giventhickness, said machine comprising box forming means including meanseffective to fold said end panel and said flap into overlyingrelationship and to secure them in that relationship, thereby to form aportion of a folded box having a double thickness, said forming meanscomprising a forming station having an entrance and reciprocating meansfor urging said blank into and through said forming station, and meansoperatively secured to an interior surface of said forming station at alocation inboard of said entrance and effective to engage saiddouble-thickness portion of said box after said box has passed thereby,thereby to prevent return movement of said folded box towards theentrance of said forming station, during the return stroke of saidreciprocating means.
 19. In a machine for forming boxes from blankshaving opposed foldable end panels and opposed foldable flaps of a giventhickness, said machine comprising box forming means including meanseffective to fold said end panel and said flap into overlyingrelationship and to secure them in that relationship, thereby to form aportion of a folded box having a double thickness, said forming meanscomprising a forming station having an entrance and reciprocating meansfor urging said blank into and through said forming station, and meansoperatively secured to an interior surface of said forming station at alocation inboard of said entrance and effective to engage saiddouble-thickness portion of said box after said box has passed thereby,thereby to prevent return movement of said folded box towards theentrance of said forming station, during the return stroke of saidreciprocating means, said double-thickness portion engaging meanscomprising a camming surface.